Typewriting-machine



0. PETERMANN.

- TYPEWRITING momma.

APPLICATION FILED JUNE 2. 191 7.

1,356, 25. Patented 0a. 26,1920..

2 SHEETS-SHEET ATTORNEYS 0; P ETERMAA IN.

TYPEWRITING MACHINE" 7 APPLICATION FILED JUNE 2. 19']- 1,356,825, rPatented Oct. 26,1920;

\ 2 SHEETS-SHEET 2- UNITED STATES PATENT OFFICE.

.orro PETERMANN, or GROTON, NEW voniggmssfeiron' '10 CORONA tryrnwmrnn'4 COMPANY, INc.-, OF GROTON, NEW YORK, I CORPORATION or NEW YORK.

rYrEwmTI e-mAcHINE.

I Application filed June 2,

citizen of the United States, and resident of Groton county of Tompkins,and State of New York, have invented certain 'new and usefulImprovements in- Typewriting-Machines, of which the following'is aspecification.

This invention relates more particularly to key actions of front-strike,visible typewriting machines. 4

One of he principal objects of the invention is to provide a key actionwhich has a very easy-and uniform touch and in which the type bars have.anupward and rearward acceleratedmovement.

"Another'object of the invention is to so construct the key action thatit will form an efficient rebound lock to effectively hold the type baragainst any reboundingmotion after the bar has returned to its point ofrest. By-providing an effective rebound lockv any form of noiselesscushioning material may be used as a stop to receive the blow or impactof the type bar on its return from its prlntin movement. In t pewritingmachines which are not provi ed with a rebound lock the type barsfrequently so move in rebounding from the type rest that when adjacenttype bars are actuated in succession they are liable to interlock. Forthis reason, it heretofore, has not been possible to use a softnoiseless cushion or pad on the type rest.

- parts of the type bar action and to dispense with the usual form ofturn buckle adjust- 1nient between the key lever and the type ar. I

.Otherobjects of theinvention are to provide -a simple and eflicient keyaction in which substantially all the'parts may be punched from sheetsteel or other suitable material," to provide means whereby the parts ofthe key 'action may be readily made and assembled, and to provide a key,action occupying a minimum amount of spaceto thereby particularly adaptit'for-small portable typewriting machines.

In the drawing, Figure tion of a key action, the supporting parts 'andthe platen being shown in sectional view Specification of LettersPatent.

1 is a sideeleva Patented Oct. 26, 1920;

1917. Serial No. 172,878.

Fig. 2 a similar view showing the type bar .in-itsprintingpositionagainst the platen; 3 ahorlzontal sectional view on the line IIIII ofFig. 1';

Fig. 4 a fragmentary plan view of a key action for a type bar located atthe left hand sidepfthe machine; L

Flg. 5 a vertical transverse sectional view on the line V-V of Fig. 4;and

Fig. 6 a view similar to Fig. 1, showing a keyaction for a type barlocated at the right hand side of the machine.

Referring-to the various parts by numerals, 1 designates the platenwhich may be supported on an suitable formof carriage; 2 the type barsegment which forms the support for the type bars, said support beingof-any suitable form or construction, and 3 I the type rest, said restbeing provided with a suitable soft cushioning material 4. The

type bar 5 is mounted at its rear end upon a pivot' 6, and carries atits forward end a type head 7, which, as shown" in the drawing, isprovided with three printing characters, It is manif st that thetypehead may be' provided wit any suitable number of printingcharacters. Below the-type ,bar, near its rear end, is suitablysupportedthe key lever fulcrum bar 8, said bar being preferably located close tothe lower edge of the type barv in order that the key action will occupya small space and be adapted for use in small portable typewritingmachines. The key lever 9 is notched on its underside at its rearend,'as at 10, to receive the edge of the fulcrum bar, as shown clearlyin 13, the said bar limiting the upward'movement of the key lever andholdin said lever in its normal or at-rest position. 'xtending,

'rea'rwardly from the part 12 is-abendable, substantially horizontaladjusting prong 14;.

To the forward end of this rong is pivoted an upwardly extending liiie15, the upper end of which-is broadened and provlded with a.horizontalfiange 16 at ri ht angles to the longitudinal line of thelini.

. Fig.

1. Thefulcrum bar is. perforated to admit engage the face of thesub-lever 19 at therearwardly extending arm 19".

"ward the pivotal point 22 of the lever.

A bell crank lever 19 is pivoted on an upwardly extending fulcrum prong17 formed integral with a sheet metal segment 18. The fulcrum prong isin the.form of a twisted tooth integral with a flange on the sheet metalsegment. Itwill be observed thatthe fulcrum-support 18 is in the form ofa sheetmetal barof channel form, the two longitudinal edge-flangesextending upwardly, one of them being deeper'than the other in order toafford sufficient metal to form the upstanding ears 17, these cars beingformed by vertically slitting the flange at intervals and twisting thelugs thus formed so that they will lie at an an le with reference to thesupporting-bar. his. results in a stiff and light fulcrum-bar which canbe manufactured at a minimum cost and which will have a minimum weight.The bell crank lever 19 is formed with an upwardly and forwardlyextending arm 19*, and with a The upwardly and forwardly. extending armof said lever is formed with a large aperture 20, the lower wall 2l ofsaid aperture forming a rearwardly and'downwa'rdly extending curvedbearing surface. The flange 16 of the link 15 extends laterallythrough-the aperture 20, its under side, in the normal at-rest positionof the key action, engaging the forwar'dmost point of the bearin surface21, as shown clearly in F ig: 1.- s the key lever is depressed theflange '16 of the link 15 progressively engagessaid bearing surface, thepoint of engagement movin tot is, therefore, manifest that as the keylever is depressed the leverage is greatest on the arm 19 at thebeginnig of the movement, and gradually grows 'less as the link movesdownwardlv, and that, therefore, the speed of movement of the lever 19will be gradually accelerated from the beginning of the downwardmovementof the key lever to the completion of said movement. The lateralflat flange 16 of the link 15 is provided with lugs 16 at its forwardand rear ends which side opposite the link 15, thereby locking the link15 against lateral withdrawal from the hole '20 in the sub-lever; and,to hold the rocklng flange 16 against fore-and-aftslid- 1ng movement onthe rocker bearing 21, the

front and rear walls of the hole 20 are positioned' so as to engage theforward and rear edges of the flange 16, thereby permitting the flangeto have a free rocking movement on the bearing 21, but at the same timepre bound. vent ng it being dislocated therefrom.

his

- ing connection between the link 15 and the sub-lever, whlch connectionwill not require any screws or pivots or other parts requiringmachine-finishing.

The rear end of the type bar is formed with a short downwardly extendingarm 23, and said arm is connected to the arm 19 of the lever 19 by ahorizontal link 24. The.

prevented by the arm 23, link 24 and,leve'r arm 19", because the forwardthrust of the arm 23 will be transmitted directly to the center of thepivot 22 of the lever 19 and there will be no upward movement of thetype bar. These parts are on centers and are locked. against movementthrough the tyIpe bar. It is manifest that this will eff'ectua lyprevent any rebound of the type bar after it has moved back to itsat-rest position. Connected to the bell-crank lever and the key leverfulcrum bar is a spring 25 which returns all the parts to theirnormal'at-rest positions upon the release of the key lever.-

26 indicates a universal bar of .any suitable construction and which isadapted'to be engaged by the key lever as it is depressed.-

he upwardly extending fulcrum prong 17 supporting the lever 19, may bereadily bent forward or rearward by any suitable device, in order toproperly adjust the connection between the rearwardly extending arm 19of the lever 19 and the forward end of the link 24. By providing thisbendable fulcrum prong proper adjustment may be made between the lever19 and arm 23 of the' type bar without the necessity of using'any otherform'of adjusting device, such, for instance, as the ordinary andwell-known turn buckle. In.order to secure the proper ad:

justment between the key lever, the link 15 and the bearing surface 21of the bell-crank lever, the prong 14 of the key lever isbendable-vertically, It is, therefore, to be noted that all of thenecessary adjustments between the several parts of the key action may besecured by bending suitably arranged lugs or prongs, thereby avoidingthe use of screws or other similar devices which arediable to be jarredoutof proper adjust- .ment in the use of the machine. ,This

method of adjusting is, especially advantageous in securing the properpositions of the parts to lock thetype' bar against .re-

I 3 In- Fig.2 the key action is-shown as ha'ving been operated to'throwthe type head on the type bar to thep rmtlng point on the platen. Theshifting of the point of 1 engagement between the flange 16 and thebearing surface 21 of the lever 19isv clearly shown in thisfigure, thesaid flange being in engagement with the point of the bearing surface 21which is nearest the pivot 22 of the completion of the printingmovement. It

is also manifest that at the start of the key lever movement the typebar movement will be slow but will respond to a very light touch. .Breason of the disposition of the link 24 and arm 19" of the bell-cranklever 19 there must be a slight movement of the lever 19 before therecan be any upward and. forward movement of the link 24. This alsocontributesflto the ease of the key action.

By reason of the arrangement of the arm 19 of the bell-crank lever, thelink 24 and the arm 23 of the type bar, the type bar will be given aprogressivelyaccelerated movement toward the platen. It is manifest thatas the arm 19 moves upwardly, its travel away from the pivotal point ofthe type bar is progressively accelerated, and that consequently thetype bar will be given the de scribed accelerated movement. It is clear,therefore, that the acceleration of the type bar will be due, first tothe shifting of the point of engagement between the link and the bearingsurface 21 of the bell-crank lever, and second by reason of the upwardand forward movement of the arm 19 of thesaid lever. By reason of this.construction and arrangement of the parts the. key stroke may be madereasonably short and the leverage of the bell-crank lever may be ofconsiderable length at the beginning of the key stroke, therebyresulting in a very easy key action.

In the drawing the movement of the type bar and the key lever. isindicated by numer-- ale and dotted lines; The downward movement of thekey lever is indicated by the numerals 0, 1, 2, 3 and 4, the horizontallines adjoining said numeralsl indicating equal parts of the downwardtravel of the said lever. The upward movement of the type bar isindicated by the numerals O, 1, 2, 3

'and 4, the spaces between said numerals indicating the distancestraveled by the type bar during the movement of the key lever /throughthe spaces between corresponding numerals. It will be noted that theupward 3 and 4, so that there is a progressive acceleration of the typebar from its rest to the platen.

It is manifest that the locking action be-' tween the type bar, link24-and bell-crank lever 19, may be secured byarranging the point ofconnection between the link 14 and the arm 19 slightly below a directline drawn between the center of the pivot 22 of the bell-crank leverand the point of' connection between the rod 24 and the arm- 23 of thetype bar. This. arrangement of the parts, while effective, will require.a slightly greater lost motion in the bell.-

crank lever before the movement thereof will actuate the type bar. Whilethe parts in this position will be slightly off centers, it will, ofcourse, be understood that the same result of locking the type baragainst rebounding.

having an upwardly and forwardly extend point of ing arm provided withan aperture the lower 1 wall of which forms a downwardly and rearwardlyextending bearing surface, the other. arm of said lever extendingrearwardly substantially horizontally, a link pivotally connected to thekey lever and formed with a substantially horizontal flange atits upperend, said flange extending through the aperture in the bell-crank leverand engaging the said bearing surface, and a substantially' horizontallink connecting the rearwardly extending arm of the bell-crank lever tothe type bar, the points bf connection between the link, type bar andbellcrank lever being in a substantially hori zontaljline and-oncenters, whereby the ty' e bar will be locked against rebound from itsat-rest position. I

2.111 .a key action the combination of a type bar, a key lever, abell-crank lever'havingan upwardly and forwardly extending armprovided'with an aperture the lower wall of which forms a downwardly andrearwardly extending bearing surface, the other arm of said leverextending rearwardly substantially horizontally, a linkpivotallyconnected to the key lever and formed with a substantiallyhorizontal flange at its upper end, said -flange extending through theaperture inthe bell crank lever and engaging the said bearingsurface,-means carried by the key lever link to'prevent itsaccidentaldisconnection from the bell-crank lever, and a substantially horizontallink connecting the rearwardly extending arm of the bell crank lever tothe type bar, the points of connection between the link, type bar and ofsaid bearing surface, and a link adapted bell-crank lever beinginasubstantially horizontal line and on centers, whereby the type bar willbe locked against rebound- 'from its at-rest position.

3. In a type-bar action, a sub-lever provided at one end with anupwardly-facing convexed bearing surface and upwardly-extending edges atthe forward and rear ends from said convexed lower edge, and a link forconnecting the sub-lever to a key-lever and having a flange extendingthrough said hole adapted to rock on said upwardly-convexed edge andprovided with lugs extend- 21 ing fore-and-aft to engage saidupwardlyextending edges to thereby detachably lock the flange to thesub-lever.

5. In a key action the combination of a type bar, a key lever formedwith a rear 81 wardly extending bendable prong, a bellcrank lever, alink connected to the bendable 'prong on the key lever and having afloating or variable connection with the bell-crank lever, and a linkconnecting the bell-crank 8! lever'to the type bar.

This spgcification signed this 24th day of May, A. 1917.

OTTO PETERMANN.

